An embodiment relates generally to in-vehicle communication diagnostics.
In-vehicle communication systems utilize a vehicle multiplex bus to allow electronic control units (ECUs) and other devices to communicate with one another. Vehicle systems and subsystems have numerous ECUs that control actuators or receive vehicle operation data from sensing devices, which is shared between the communicating ECU.
A communication protocol is a system of digital message formats and rules for exchanging those messages in or between communication devices within the network. The in-vehicle communication system includes a transmitting node, at least one receiving node, and a network communication bus coupling the transmitting node to the at least one receiving node. Each of the transmitting nodes and the at least one receiving node includes a plurality of communication layers for servicing messages within each of the nodes within the in-vehicle communication system. The plurality of communication layers typically control the message transfer by providing rules as to how the message is formatted and how the message is exchanged.
The communication network is typically active (i.e., powered) when communications are ongoing, and is deactivated when no communications are transmitted on the communication bus. When in a deactivated state, the communication network enters a sleep mode to conserve power. This typically occurs when the vehicle is turned off. If an error occurred in the system where the network remained active after it was assumed to be inactive by all the network devices, then undesirable battery drain could occur as a result of the system being unintentionally powered.